EXPERIMENTAL CHARACTERISTICS OF RUBBERIZED CONCRETE

One of the construction industry’s main interests is using innovative materials to facilitate construction, extend service life, and minimize maintenance and rehabilitation costs. Recycling waste tire rubbers into conventional concrete materials constitutes one of the biggest and challenging issues in modern concrete technology, which can significantly relieve critical environmental issues. However, the compressive strength reduction caused by the added rubber aggregates, albeit with significant ductility enhancement, has limited its application in concrete structures. The present study aimed at attaining the optimum ratio of crumb rubber with minimal reduction in compressive strength to be used in large scale elements in which the ductility constitutes a critical design parameter. Different rubberized concrete mixes with different percentages of crumb rubber (CR) and different treatment were investigated. The main parameters were the type of crumb rubber (course or fine), the percentage of replacement (5%, 10%, 20%, and 30%), the treatment conditions (treated with NAOH, or without treatment), and using silica fume as partial replacement of cement. The test data were analyzed considering the workability, the compressive, tensile, and flexural strengths. The results revealed that the most appropriate concrete mix is using a 20% treated fine crumb rubber, with silica fume incorporation.